Sclerotherapy for Leg Veins in London: A Dermatologist-Led Treatment for Thread and Spider Veins on the Legs
Sclerotherapy London
By Dr Hiba Injibar | Consultant Dermatologist, Dermasurge Harley Street
Thread and spider veins on the legs are extremely common, and they rarely behave the way patients expect. You might notice a cluster of fine red or blue veins behind the knee, a web of them across the thigh, or a scattering along the ankle that becomes more obvious after a summer of bare legs. They are not painful in most cases, but they can be persistent and difficult to disguise, and no amount of topical cream will clear them. This is a structural change within small blood vessels, which is why creams and serums make no difference.
Sclerotherapy is the established medical treatment for these veins. At Dermasurge Clinic, it is carried out within a consultant-led dermatology practice, which means assessment comes first and treatment follows a clear clinical rationale. This article explains how microsclerotherapy works for leg veins specifically, who it suits, and what realistic recovery looks like.
What is sclerotherapy?
Sclerotherapy is a treatment in which a medical solution, known as a sclerosant, is injected directly into an unwanted vein using a very fine needle. The solution irritates the lining of the vessel, causing it to collapse and seal. Over the following weeks, the treated vein is gradually reabsorbed by the body and fades from view. Blood that previously travelled through it is simply rerouted through healthier vessels, which is why removing these small superficial veins has no impact on your circulation.
When the technique is used for the small thread and spider veins found on the legs, it is often called microsclerotherapy, reflecting the very fine needles and small volumes involved. It is one of the most widely studied treatments for leg telangiectasia, and it remains the recognised first-line approach for these superficial vessels.
Leg veins are not the same as facial thread veins
This is an important distinction, and one that affects which treatment is appropriate. Facial thread veins, the fine red vessels that often appear around the nose and cheeks, are usually treated with laser or intense pulsed light rather than injection. The skin on the face is delicate, the vessels sit very superficially, and light-based platforms tend to give a cleaner result there. We cover facial vessels separately in our guidance on thread vein treatment.
Leg veins behave differently. They are often slightly larger, sit under thicker skin, and are frequently connected to small feeding vessels beneath the surface. For most leg thread and spider veins, injection sclerotherapy reaches the problem more effectively than light alone. The two areas genuinely call for different tools, which is one reason a proper assessment matters before anything is booked.
Who is sclerotherapy suitable for?
Sclerotherapy suits adults troubled by visible thread veins (sometimes called spider veins or telangiectasia) on the thighs, calves, ankles or behind the knees. Most people who seek treatment do so for cosmetic reasons, although some report mild aching or a feeling of heaviness in the affected area.
You are likely to be a suitable candidate if:
- You have superficial red, blue or purple thread veins on the legs that have not responded to anything you have tried.
- You are in good general health and not pregnant or breastfeeding.
- You understand that more than one session may be needed and that results develop gradually.
Sclerotherapy is generally not carried out during pregnancy, in part because pregnancy-related veins often improve on their own afterwards. It is also less suitable for anyone with certain clotting disorders, a history of deep vein thrombosis, or particular circulatory conditions, which is exactly why a medical assessment precedes treatment.
When leg veins point to something deeper
Some leg veins are a surface sign of underlying venous insufficiency, where the valves in larger veins are not working efficiently. If prominent varicose veins, significant swelling or skin changes around the ankle are present, treating the surface vessels in isolation is unlikely to give a lasting result, and onward investigation or referral may be more appropriate. A consultant dermatologist is well placed to recognise these patterns and advise accordingly, rather than proceeding with injections that would not address the real cause. This is a key advantage of a consultant-led pathway over a treatment booked on appearance alone.
How dermatology approaches leg vein treatment
The starting point is always assessment, not the needle. At Dermasurge, the consultation involves examining the legs in good light, mapping the pattern of veins, and asking about symptoms, medical history and any previous vein treatment. The aim is to confirm that the vessels are suitable for sclerotherapy and to rule out signs of deeper venous disease.
From there, you receive a personalised treatment plan. This sets out how many sessions are likely to be useful, the realistic degree of clearance you can expect, and what the recovery looks like for your particular pattern of veins. Honest expectation-setting is part of the clinical process. Sclerotherapy can produce a marked improvement in the appearance of treated veins, but it is rarely a single-session fix, and new veins can appear over time independently of the ones treated.
What happens during a session
A sclerotherapy session is carried out in the clinic and typically takes between fifteen and forty-five minutes, depending on how many veins are being addressed. You remain awake throughout, and no general anaesthetic is involved.
Using a very fine needle, the sclerosant is injected into each target vein. Most patients describe the sensation as a small sting or a brief cramping feeling rather than significant pain. Once the relevant area has been treated, compression is usually applied, either with a dressing or a compression stocking, to support the treated vessels as they begin to close.
How many sessions are usually needed?
Most patients need more than one session to achieve the result they are after. Veins respond at different rates, and treating an area in stages allows the dermatologist to assess how the vessels are settling before deciding what to address next. Sessions are typically spaced several weeks apart. The exact number depends on the extent and density of the veins, which is established at your consultation rather than guessed in advance.
Recovery and what to expect afterwards
Sclerotherapy involves very little downtime, and most people return to their normal day straight away. There are, however, some expected after-effects, and knowing about them in advance prevents unnecessary worry.
- Compression. You will usually be advised to wear a compression stocking for a period after treatment, often for a number of days. This helps the treated veins close and can improve the final outcome.
- Walking and activity. Gentle walking is encouraged. Strenuous exercise, long-haul flights, very hot baths and saunas are generally avoided for a short period, as advised in your aftercare plan.
- Bruising and marks. Small bruises, slight redness or raised areas around the injection sites are common and settle over days to a few weeks.
- Pigmentation. Some patients notice temporary brownish lines along the path of treated veins, caused by iron pigment from the blood. This usually fades over weeks to months, though it can occasionally persist longer.
- Matting. Occasionally, fine new vessels appear near a treated area. These can often be addressed at a later session.
Results develop gradually. The treated veins do not vanish on the day; they fade as the body reabsorbs them over the following weeks. This is why follow-up review is built into the plan, allowing progress to be assessed before any further treatment is arranged.
Why choose Dermasurge Clinic
Leg vein treatment is widely advertised across London, often in settings where no medical assessment takes place beforehand. The difference at Dermasurge is the clinical context. Treatment is led by Dr Hiba Injibar, a consultant dermatologist on the GMC specialist register, so the same diagnostic rigour applies to a cosmetic concern as to a medical one. If your leg veins are a sign of something that needs investigation rather than injection, that will be recognised and discussed openly.
Dermasurge offers both medical and cosmetic dermatology under one roof, which matters when a concern sits on the boundary between the two. The clinic also houses on-site laser and light platforms, including M22, Q-switched and IPL systems, so where a light-based approach is genuinely better suited (as it often is for facial vessels), that option is available and is recommended on clinical grounds rather than on what is being marketed. Every plan is evidence-based and personalised to the individual rather than applied as a fixed protocol. You can read more about the breadth of consultant-led dermatology at Dermasurge Clinic across both medical and cosmetic care.
If you are considering treatment, the first step is to arrange an assessment with a consultant dermatologist who can confirm whether sclerotherapy is appropriate for your legs.
Frequently asked questions
Is sclerotherapy painful?
Most patients find sclerotherapy well tolerated. The needles used are very fine, and the sensation is usually described as a brief sting or a mild cramping feeling as the sclerosant enters the vein. Because no anaesthetic injection or sedation is needed for the treatment itself, you can return to your normal activities the same day in most cases.
How long do the results last?
Once a vein has been successfully treated and reabsorbed, it does not return. However, sclerotherapy does not stop new thread or spider veins from developing elsewhere over time, particularly if there is an underlying tendency towards them. Many patients choose periodic maintenance sessions to address new veins as they appear. Your dermatologist will give you a realistic picture based on your individual assessment.
Can I have sclerotherapy on facial veins too?
Facial thread veins are usually better treated with laser or intense pulsed light rather than injection, because of the delicacy of facial skin and the way the vessels sit. Sclerotherapy is primarily used for leg veins. At your consultation, the consultant dermatologist will advise which approach is appropriate for each area, and the clinic has both options available on site.
How soon will I see a difference after treatment?
Results develop gradually rather than immediately. Treated veins fade over the weeks that follow as the body reabsorbs them, and the full effect of a session is usually assessed several weeks later. Temporary bruising or brownish marks may be visible in the early stages, so it is best not to judge the outcome too soon. Most patients are reviewed before any further treatment is planned.
Is sclerotherapy safe?
Sclerotherapy is a well-established treatment with a long track record when carried out by an appropriately trained practitioner after proper assessment. As with any medical procedure, there are potential side effects, including bruising, temporary pigmentation and, less commonly, matting or inflammation at the site. A thorough consultation identifies anyone for whom the treatment would not be suitable, which is central to keeping it safe.
Booking your assessment
Assessment with a consultant dermatologist is required to determine whether sclerotherapy is the appropriate treatment for your leg veins. This ensures the cause is correctly understood before any treatment begins and that your plan is tailored to your skin and your circulation.
To discuss thread and spider veins on the legs with a GMC-registered consultant dermatologist, book a consultation at Dermasurge Clinic.
